dvb-vbi

VBI (Vertical Blanking Information) data carriage in DVB — ETSI EN 301 775 §4, the PES data field: VPS, WSS, Closed Captioning, EBU / Inverted Teletext, and generic monochrome 4:2:2 luminance sample data units.

VBI data is carried in the private PES packet mechanism (stream_id = private_stream_1 0xBD); this crate decodes the data field that follows the PES header.

Implements:

• DataField — the PES data field (§4.4.1, Table 1): a data_identifier byte (Table 2) followed by a loop of data units.
• DataUnit / DataUnitId — each data unit's data_unit_id (Table 3)
  • 8-bit data_unit_length + typed body. data_unit_length is recomputed from the typed body on serialize (no raw passthrough).
• TeletextDataField — EBU (0x02/0x03) and Inverted (0xC0) Teletext (§4.5): a shared LineHeader + an 8-bit framing_code + a 42-byte opaque txt_data_block. EN 300 706 Teletext coding is out of scope.
• VpsDataField — VPS (0xC3, §4.6): shared header + 13-byte data block.
• WssDataField — WSS (0xC4, §4.7): shared header + a 14-bit wss_data_block + a 2-bit reserved_future_use 11 tail (3 bytes total).
• ClosedCaptioningDataField — Closed Captioning (0xC5, §4.8): shared header + a 16-bit data block (line 21, EIA-608 Rev A).
• MonochromeDataField — monochrome 4:2:2 samples (0xC6, §4.9): its own first-byte packing (first/last segment flags + field_parity + line_offset), a first_pixel_position, n_pixels, and the luminance Y_value bytes.
• Stuffing (0xFF, §4.4.1) and an Opaque catch-all for reserved / user-defined ids round-trip verbatim.

The shared LineHeader is the Teletext/VPS/WSS/CC first byte (reserved_future_use 11 | field_parity | 5-bit line_offset).

⚠ Table 1's parse branch routes data_unit_id 0xC1 to txt_data_field(), but Table 3 marks 0xC1 as reserved → discard. This crate follows Table 3 (authoritative), so 0xC1 decodes as DataUnitId::Reserved.

#![no_std] + alloc; depends only on broadcast-common.

Quick start

use dvb_vbi::{DataField, DataUnit, LineHeader, VpsDataField, WssDataField};

let vps = DataUnit::vps(VpsDataField {
    header: LineHeader::new(true, 16),
    vps_data_block: [0u8; 13],
});
let wss = DataUnit::wss(WssDataField {
    header: LineHeader::new(true, 23),
    wss_data_block: 0x1234,
});
let field = DataField::new(0x10, vec![vps, wss]);

let mut buf = vec![0u8; field.serialized_len()];
field.serialize_into(&mut buf).unwrap();
assert_eq!(DataField::parse(&buf).unwrap(), field);

Examples

cargo run -p dvb-vbi --example build_data_field
cargo run -p dvb-vbi --example parse_data_field

Features

Minimum Supported Rust Version

1.95.0

License

MIT OR Apache-2.0